When paints which include a glitter-material which has an angle-dependent interference effect have been used in the past the change in the interference color of the mirror reflected light obtained by changing the viewing angle of the paint film which has been formed from a face angle to a grazing angle has been just a change from a chromatic color to a chromatic color of a different hue, and an effect of changing from an achromatic color at a facing angle to a chromatic color at a grazing angle has not been obtained.
For example, dichroic paint compositions which include (1) a vehicle, (2) a metal oxide coated silica flake pigment and, as required, (3) a glitter pigment and/or coloring pigment are known as dichroic paint compositions which can exhibit stable dichroism which provides colors which differ according to the viewing angle (see Patent Citation 1). However, when the viewing angle from which the paint film is seen after painting is shifted from right above at more or less 90° which is a face angle to about 15° which is a grazing angle the effect of changing from an achromatic color to a chromatic color is not obtained.
Furthermore, glitter paint compositions which are clear paint compositions which contain vehicle and two or more types of interference glitter pigment and one of the abovementioned two or more types of interference glitter pigment is an interference glitter pigment (a) of average particle diameter from 5 to 10 μm and the other type is an interference glitter pigment (b) which has an average particle diameter from 10 to 30 μm and manifests a interference color different from that of the interference pigment (a), and in which the relationship (c) that {average particle diameter of interference glitter pigment (b)−average particle diameter of interference glitter pigment (a)=from 10 to 25 μm} exists are known as glitter paint compositions which can manifest a design of three colors depending on the angle from which the paint film is seen (see Patent Citation 2). However, although with a paint film which has been formed from this glitter paint composition the color differs according to the viewing angle, but the saturation in the highlight is higher than the saturation in the shade and an effect such that it becomes an achromatic color at a face angle and a chromatic color at a grazing angle is not obtained.
Furthermore, glitter paint compositions which include (a) a first glitter pigment where the whole surface of a thin leaf-like base material has been essentially coated with a layer in which a colored pigment has been dispersed in a matrix which has silicon oxide as the main component, (b) a second glitter pigment comprising a glitter pigment which is different from the first glitter pigment and (c) a vehicle and in which the total amount of the aforementioned first and second pigments included as the pigment mass content (PWC) is from 1 to 30% is known as a paint composition with which a paint film which has a sense of high saturation in the highlight parts and some depth of a sense of faded whiteness in the shade parts due to a synergistic effect of the colored glitter pigment with a high selective color region and the other glitter pigment can be obtained (see Patent Citation 3). However, the paint films formed from this glitter paint composition have a high saturation in the highlights and a low saturation in the shade but they do not provide an effect such that they have an achromatic color at the face angle and chromatic color at a grazing angle. Furthermore the color of the paint film at a grazing angle is an achromatic color which is deep black and the color when seen at a face angle is a chromatic color and this is different from the novel design which is the intention of the inventors of the present application.
Furthermore, a method of forming a laminated pearl paint film which includes a process in which a mica base paint film is formed on a base material on which an undercoat paint film and a mid-coat paint film have been formed; a process in which a clear paint film is formed over the top without curing the mica base paint film; and a process in which the mica base paint film and the clear paint film are cured by heating which is characterized in that the mica base paint from which said mica base paint film is formed contains titanium oxide coated silica flakes with a pigment weight concentration (PWC) in the range from 1 to 18%, and the brightness of said laminated pearl paint film as the L value is from 0 to 30 is known as a method for obtaining laminated pearl paint film in which the phenomenon of the low-color parts becoming white (becoming an achromatic color) when seen from a shade position which occurs in an interference mica pigment containing paint film is suppressed using the titanium dioxide coated silica flakes and which has an excellent sense of transparency (see Patent Citation 4). However, these laminated pearl paint films have a high saturation in the highlights and a low saturation in the shade, and they do not provide an effect such that they become an achromatic color at a face angle and a chromatic color at a grazing angle. Furthermore, the color of the paint film at a grazing angle is an achromatic color which is a deep black and the color when seen from the face angle is a chromatic color and they are different from the novel design which is the intention of the inventors of the present invention.
Furthermore, a glitter paint composition containing vehicle, interference glitter pigment and composite oxide fired pigment in which, when the hue of the interference color of the aforementioned interference glitter pigment is set to the hue 0 in the Munsell representation system and, for a Munsell hue ring pf 100, counterclockwise rotation is +50 and clockwise rotation is −50, the hue H of the interference color of the composite oxide fired pigment is within the hue range from +30 to +50, or from −30 to −50, is known as a glitter paint composition with which it is possible to form paint films with which a sense of high saturation is obtained in the shade parts, the color difference between the highlight parts and shade parts is enhanced, it is possible to realize polychromatic designs, and with which a more sophisticated sense of glitter can be obtained (see Patent Citation 5). However, by adding a colored pigment to the interference glitter pigment the paint films which are formed are such that the color at a face angle is greatly affected by the hue of the colored pigment which has a higher coloring power than the glitter pigment, and the effect of being an achromatic color at a face angle and a chromatic color at a grazing angle is not obtained.
Furthermore, a paint composition which contains per 100 parts by weight of film-forming binder (A), from 0.1 to 15 parts by weight of (B) metallic powder, from 0.1 to 10 parts by weight of (C) a first colored pigment of primary particle size from 0.01 to 0.2 μm selected from among the phthalocyanine, perylene, indanthrone, azmethine, benzimidazolone, quinacridone, anthraquinone, diketopyrrolopyrrole and dioxazine pigments and from 0.5 to 50 parts by weight of (D) a second colored pigment of primary particle size from 0.1 to 2 μm selected from among the diketopyrrolo-pyrrole, quinacridone, pyrazolone, naphthol AS, iron oxide and composite metal oxide pigments, and in which the primary particles of pigment (C) are relatively smaller than those of pigment (D) and the pigment (C) and the pigment (D) have the relationship of complementary colors is known as a design metallic paint in which the complementary color relationship of the pigments is utilized (see Patent Citation 6). However, the effect of being an achromatic color at a face angle and a chromatic color at a grazing angle is not obtained with the paint films formed from this paint composition.